John miles moffat



(No Model.)

J.-M. MOFFAT. SOCKET AND SWITCH FOR INGANDESOENT LAMPs.

No. 569,931; Patented 009. 20, 1896.

Imnfar JOHN MILES MOFFAT,

OF LONDON, ENGLAND.

SOCKET AND SWITCH FOR INCANDESCENT LAMPS.

SPECIFICATION forming part of Letters Application filed October 15,1895- Serial No. 565,784. (No

France April 3,1895,N0.246,360.

To aZZ whom it may concern;

Be it known that 1, JOHN MILES MOFFAT, electrician, a citizen of England, residing at 100 Victoria Street, Westminster, London, in the county of London, England,have invented a certain new and useful Improvement in Electrical Glow-Lamps, (for which I have obtained a patent in France, dated April 3, 1895, No. 246,360, and in Great Britain, dated April 16, 1894, No. 7,530,) of which the following is a specification.

This invention relates to a simple and compact construction of switch in combination with the cap and socket of an electrical glowlamp, whereby a single filament, or the one or both of a pair of filaments, in the bulb can be put into or out of circuit with the conductors. For this purpose, as shown in plan in Figure 1 and in section on X X in Fig. 2 of the accompanying drawings, there are provided within the cap A of the glow-lamp B a pair of springs O D, the one, C, carrying one of the plates, E, which bear on the springplungers, which are usually provided in the socket, the other, D, connected to one of the leading-in wires of the filament, while the other leading-in wire is connected to the other plate, F. Between the springs O D there is fitted to slide a rod or wire G, the ends of which project through the cap and serve as the studs which engage in the ordinar bayonet-catch notches of the socket. On this rod or wire G is an insulated projecting metallic part H, which by pushing the wire G may be made, as indicated by dotted lines in Fig. 1, to press against the two springs O D, thereby making electrical connection from the leading-in wire to the plate to which it is was not otherwise connected, and so bringing the filament into circuit. By pushing the wire back this connection is broken and the filament is excluded from the circuit.

When there are two filaments in the bulb, the leading-in wires for one of them are connected as above described. Those of the other are connected in the usual way to the plates of the cap, which bear againt the spring-plungers of the socket. In this case the switch serves to kindle or extinguish only the one of the two filaments. If the leading-in wires for both filaments are connected as first described, the switch serves to kindle or extin guish both.

Fig. 3 shows a construction of switch in Patent No. 569,931, dated October 20, 1896. model.) Patented in England April 16, 1894, No. 7,530, and in combination with a lamp-socket, as already described, but in this case the connections with the two lamp-filaments L L are shown. The three springs O, O, and D serve to conments, L L, according as to whether the sliding rod G and its contact-piece H are pushed more or less thro ugh the holder in the direction of the arrow. On pushing the rod G still farther both lamp-filaments are disconnected.

Having thus described the nature of this invention and the best means I know of carrying the same into practical effect,l claim In an electric lamp, the combination with the cap having conducting-plates E and F arranged for connection with the socket terminals, of the springs O and D having their free ends separated but in alinement with each other, the spring O being connected with the plate E and the spring D being connected to one of the leading-in Wires, the other leadin gill wire being connected to the plate F, and a longitudinally-movable rod G provided intermediate its ends with an insulated conducting projection H and arranged to be slid into contact with the ends of both said springs when the rod is moved in one direction and out of contact therewith when the rod is moved in the opposite direction, substantially as described.

2. I11 an electric lamp, the combination with the cap having conducting-plates E and F arranged forconnection with the socket terminals, of the springs O, D and O, the spring 0 being connected to the plate E, two filaments L and L respectively connected at one .end to the springs D and C and at their opposite ends to the plate F, and a longitudinally-movable rod G provided intermediate its ends with an insulated conducting projection 11 and arranged to be moved into contact with the springs to complete the circuit through the filaments L or L separately or through both of said filaments in parallel, substantially as described.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, this 3d day of October, A. D. 1895.

JOHN MILES MOFFAT.

nect either the one filament, L, or the two fila- 

